69 Merc Tower of Power 1125 Timing, Spark or Carb?

cjleigh

Cadet
Joined
May 12, 2010
Messages
11
I have a 1969 1125 that recently shredded the timing belt. I replaced the belt following the procedures. Now since the belt replacement the motor starts but runs really rough, and sometimes seems to miss. I have read over and over on these forums not to make any kind of adjustments, so I am just looking for some advice on how to procede.

Some more information:

The wires to the plugs all check out, I ran my fluke meter on them and they are all perfect.

I replaced all the plugs with brand new L-20V's. The manual calls for L-19V's but it already had the L-20's installed prior to the belt problem and the motor ran like a top.

I ran the motor for about 15 minutes on muffs. (I am pretty far away from the lake). In that 15 minutes the motor would run rough, and then die. It would start immediatly, run for a moment and then die. This process repeated a couple of times and then I got about a 5 minute constant run, albeit rough, before shutting her down for the night. During that 5 minutes I gave it a little throttle and it seemed to smooth out, but there were some jumps as if a cylinder might be missing. I didn't check the tach, I can do that tomorrow if need be. I had to shut it down for the night because of the hour. Right after the run I pulled the plugs and inspected them. 2-6 were oily, but #1 was black and sooty.

Now I have always been taught that black and sooty indicates a rich running cylinder, but shouldn't #2 be black and sooty too if they are running off the same carb?

I am looking for advise, instructions, suggestions, etc... here. Anything that will help get this motor back to it's former glory. Do I need to make timing adjustments? Carb adjustments? Try a diffrent plug? Or just give up and take this thing to a real professional?

Thanks in advance for your help. Please let me know if there is any other information I can gather for you.
 

Fuzzytbay

Chief Petty Officer
Joined
Jun 6, 2008
Messages
557
Re: 69 Merc Tower of Power 1125 Timing, Spark or Carb?

If you changed the belt, then its possible its not lined up correctly. Double check that the line on the flywheel lines up with the mark on the distributor pully. Also you may now need to do a link and sync on the motor.
 

cjleigh

Cadet
Joined
May 12, 2010
Messages
11
Re: 69 Merc Tower of Power 1125 Timing, Spark or Carb?

I don't know what happened, but I started it today, and it's running like a top. Cleaned the plugs, and ran it for 45 minutes on the muffs, and the plugs all came out the same, no more black and sooty. Even better the motor runs smooth and even.

I don't know what the chalk this mystery up to, but I'm glad the fiasco is over. Now I wish I knew what was causing the problem in the first place so I know for the future. The world may never know.

C.J.
 
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